Herpes simplex virus types 1 and 2 are major human pathogens that primarily cause infections of the oral-facial, ocular or genital mucosal areas, and establish lifelong infections that can result in reactivation at the respective mucosal sites where the primary infection was initiated (Roizman and Spears, 1996). HSV-1 appears to be particularly damaging to the nervous system and increases the risk of developing Alzheimer's disease. The HSV virus interacts with the components and receptors of lipoproteins, which may lead to the development of Alzheimer's disease. (Dobson and Itzhaki, 1999.) This research identifies HSVs as the pathogen most clearly linked to the establishment of Alzheimer's. (Pyles R B, November 2001). A major strategy to break the cycle of transmission is the potential usage of an effective vaccine as a prophylaxis method of choice for controlling the spread of HSV.
Extensive studies have been conducted on HSV replication and pathogenesis, in particular in animal models. A variety of vaccine strategies have been tested in varied animal models, including subunit and whole virus vaccines, with encouraging results (Awasthi et al., 2011; Bernstein et al, 2011; Chan et al., 2011). However, clinical trials in humans with HSV vaccines have met with limited success (Corey et al., 1999; Ashley et al., 1985; Zarling et al., 1988). A consensus on the optimal vaccine needs to engage all the respective arms of the immune response, including Th1, Th2 and Th17 along with the presence of neutralizing antibodies, and mucosal antibodies (IgA).
Subunit vaccines have been tested utilizing individual HSV surface antigens, including gB (Allen et al, 2010), gC (Awasthi et al, 2009; Chang et al., 2005), gD (Bernstein et al., 2010) and gE (Ghiasi et al., 2992). In addition, whole HSV attenuated vaccine and subunit vaccines when tested in humans did not produce sufficient mucosal antibodies (IgA) at the appropriate surfaces, in addition T cell responses was lower that the mucosal surfaces, which is important for HSV infections and potential reactivation (Parr and Parr, 1999).
In the various HSV immunization studies, the use of the appropriate animal model is important to replicate the natural pathogenic process, as Th1 immune response is a crucial component for protection against potential reinfection and viral reactivation (Dasgupta et al., 2011).
The lack of an adequate vaccine for human use prompted the inventors to elaborate on previous findings regarding the novel features of a nanoemulsion as an immune enhancer for antigens. Use of traditional adjuvant has been added to HSV subunit vaccines without apparent efficacy in the clinical settings (Bernstein et al., 2011; Corey et al., 1999; Dasgupta et al., 2011; Ashley et al., 1985). However, a nanoemulsion, whilst providing an adjuvant effect, also helps in antigen presentation by attracting the appropriate cell types and activating multiple arms of the immune response. (Hamouda et al., 210; Bielinska et al., 2010; Makidon et al., 2008).
As with most vaccines, greater immunogenicity is also sought as it correlates with greater efficacy in humans. The prior art has typically disclosed the use of recombinant proteins (e.g., U.S. Pat. Nos. 7,192,595; 6,194,546; 5,962,298), as well as the addition of adjuvants such as aluminum (U.S. Pat. No. 6,861,244) and muramyldipeptide (U.S. Pat. No. 4,826,687) to compositions to increase the immunogenicity. However, there still exists a need to develop highly effective HSV vaccines with improved storage stability and ease of administration, which are characteristics of the nanoemulsion vaccines of the present invention.
Prior teachings related to nanoemulsions are described in U.S. Pat. No. 6,015,832, which is directed to methods of inactivating Gram-positive bacteria, a bacterial spore, or Gram-negative bacteria. The methods comprise contacting the Gram-positive bacteria, bacterial spore, or Gram-negative bacteria with a bacteria-inactivating (or bacterial-spore inactivating) emulsion. U.S. Pat. No. 6,506,803 is directed to methods of killing or neutralizing microbial agents (e.g., bacterial, virus, spores, fungus, on or in humans using an emulsion. U.S. Pat. No. 6,559,189 is directed to methods for decontaminating a sample (human, animal, food, medical device, etc.) comprising contacting the sample with a nanoemulsion. The nanoemulsion, when contacted with bacteria, virus, fungi, protozoa or spores, kills or disables the pathogens. The antimicrobial nanoemulsion comprises a quaternary ammonium compound, one of ethanol/glycerol/PEG, and a surfactant. U.S. Pat. No. 6,635,676 is directed to two different compositions and methods of decontaminating samples by treating a sample with either of the compositions. Composition 1 comprises an emulsion that is antimicrobial against bacteria, virus, fungi, protozoa, and spores. The emulsions comprise an oil and a quaternary ammonium compound. U.S. Pat. No. 7,314,624 is directed to methods of inducing an immune response to an immunogen comprising treating a subject via a mucosal surface with a combination of an immunogen and a nanoemulsion. The nanoemulsion comprises oil, ethanol, a surfactant, a quaternary ammonium compound, and distilled water. US-2005-0208083 and US-2006-0251684 are directed to nanoemulsions having droplets with preferred sizes. US-2007-0054834 is directed to compositions comprising quaternary ammonium halides and methods of using the same to treat infectious conditions. The quaternary ammonium compound may be provided as part of an emulsion. US-2007-0036831 and US 2011-0200657 are directed to nanoemulsions comprising an anti-inflammatory agent. Other publications that describe nanoemulsions include U.S. Pat. No. 8,226,965 for “Methods of treating fungal, yeast and mold infections;” US 2009-0269394 for “Methods and compositions for treating onychomycosis;” US 2010-0075914 for “Methods for treating herpes virus infections;” US 2010-0092526 for “Nanoemulsion therapeutic compositions and methods of using the same;” US 2010-0226983 for “Compositions for treatment and prevention of acne, methods of making the compositions, and methods of use thereof;” US 2012-0171249 for “Compositions for inactivating pathogenic microorganisms, methods of making the compositions, and methods of use thereof;” and US 2012-0064136 for “Anti-aging and wrinkle treatment methods using nanoemulsion compositions.” However, none of these references teach the methods, compositions and kits of the present invention.
In particular, U.S. Pat. No. 7,314,624 describes nanoemulsion vaccines. However, this reference does not teach the ability to induce a protective immune response to HSV using the immunogens of the invention.
Prior art directed to vaccines includes, for example, U.S. Pat. No. 7,731,967 for “Composition for inducing immune response” (Novartis), which describes an antigen/adjuvant complex comprising at least two adjuvants. U.S. Pat. No. 7,357,936 for “Adjuvant systems and vaccines” (GSK) describes a combination of adjuvant and antigens. U.S. Pat. No. 7,323,182 for “Oil in water emulsion containing saponins” (GSK) describes a vaccine composition with an oil/water formulation. U.S. Pat. No. 6,867,000 for “Method of enhancing immune response to herpes” (Wyeth) describes a combination of viral antigens and cytokines (IL12). U.S. Pat. No. 6,692,752 for “Methods of treating human females susceptible to HSV infection” (GSK) describes a method of treating an HSV 1-/2-female human subject susceptible to herpes simplex virus (HSV) infection. The method comprises administering to the subject an effective amount of a vaccine formulation comprising an adjuvant and an antigen which is or is derived from the group consisting of HSV-1 glycoprotein D, HSV-2 glycoprotein D and an immunological fragment thereof. U.S. Pat. Nos. 6,623,739, 6,372,227, and 6,146,632, all for “Vaccines” (GSK), are directed to an immunogenic composition comprising an antigen and/or antigen composition and an adjuvant consisting of a metabolizable oil and alpha tocopherol in the form of an oil in water emulsion. U.S. Pat. No. 6,451,325 for “Adjuvant formulation comprising a submicron oil droplet emulsion” (Chiron) is directed to an adjuvant composition comprising a metabolizable oil, an emulsifying agent, and an antigenic substance, wherein the oil and emulsifying agent are present in the form of an oil-in-water emulsion. The adjuvant composition does not contain any polyoxypropylene-polyoxyethylene block copolymer; and the antigenic substance is not present in the internal phase of the adjuvant composition. U.S. Pat. No. 6,027,730 for “HSV gD and 3 deacylated monophosphoryl lipid A” (GSK) describes a vaccine formulation comprising a Herpes Simplex Virus glycoprotein D or an immunological fragment of the Herpes Simplex Virus glycoprotein D, 3 Deacylated monophosphoryl lipid A and a carrier. The carrier is alum or an oil in water emulsion. U.S. Pat. No. 5,747,039 for “Recombinant herpes simplex gB-gD vaccine” (Chiron) describes a method for immunizing a human against herpes simplex virus (HSV) infection comprising vaccinating the human with an adjuvant and a vaccine formulation consisting essentially of HSV polypeptides. The HSV polypeptides are immunogenic, glycosylated, and consist of (i) a HSV glycoprotein B polypeptide or a HSV glycoprotein B polypeptide that has a deletion of all or a portion of the transmembrane anchor region; and (ii) a HSV glycoprotein D polypeptide or a HSV glycoprotein D polypeptide that has a deletion of all or a portion of the transmembrane anchor region. U.S. Pat. No. 5,648,079 for “HSV gB Vaccine” (Chiron) describes a vaccine composition comprising a recombinantly produced glycosylated glycoprotein B (gB) polypeptide of Herpes Simplex Virus (HSV) that has a deletion of all or a portion of the transmembrane anchor region, in combination with a pharmacologically acceptable carrier and an adjuvant. U.S. Pat. No. 5,612,041 for “Recombinant HSV gD vaccine” (Chiron) describes a method for alleviating recurrent Herpes Simplex Virus (HSV) infection in a human comprising vaccinating the human subsequent to HSV infection with a vaccine consisting essentially of an adjuvant and a protein selected from the group consisting of glycoprotein D (gD) of HSV and a C-terminally truncated form of HSV gD which lacks all or a portion of the anchor sequence coding region. U.S. Pat. No. 5,171,568 for “Recombinant HSV gB-gD vaccine” (Chiron) describes a vaccine formulation consisting essentially of herpes simplex virus (HSV) polypeptides wherein the HSV polypeptides are immunogenic, glycosylated, and consist of: (i) a HSV glycoprotein B polypeptide or immunogenic fragments thereof; and (ii) a HSV glycoprotein D polypeptide or immunogenic fragments thereof. US 20110177125 for “HSV combined subunit vaccines and methods of use thereof” (U Penn-Friedman) describes a vaccine comprising a recombinant HSV-2 gD protein or immunogenic fragment thereof, a recombinant HSV-2 gC protein fragment, and an adjuvant. The HSV-2 gC protein fragment comprises a C3b-binding domain thereof, a properdin interfering domain thereof, a C5 interfering domain thereof or a fragment of the C3b-binding domain, properdin interfering domain, or C5-interfering domain. Finally, US 20040151734 for “Vaccine and method of use” (GSK) describes a method of treating a female human subject suffering from or susceptible to one or more sexually transmitted diseases (STDs). The method comprises administering to a female subject in need thereof an effective amount of a vaccine formulation comprising one or more antigens derived from or associated with an STD-causing pathogen and an adjuvant.
There remains a need in the art for an effective HSV vaccine and methods of making and using the same. The present invention satisfies these needs.